I doubt we'll see necromancer in name. We already know of one necromancer in Eorzea, Nybeth Obdilord, the boss of PotD floor 100 and it's clearly a caster type job with control over the undead and the ability to raise them.
I could see something that resemble a necromancer, but not an undead raising type.
Raising the dead as undead is very taboo in Eorzea, especially in Ul'Dah after the war with Sil'Dih.